I'm trying to enter times for a swim team I help coach. So the format is either mm:ss.0 or ss.0. Excel keeps converting it to a time of day, making it impossible to do the sorting I want it to. I have tried numerous times to change it to my custom format, but nothing happens. I have also tried converting them to plain text and general numbers, as well as just replacing every colon with a period. Everything I try either has no effect or just sends it all to Hell.

Please help or send gifs because I am so frustrated I am in tears.